Skip to main content

Too many carbs and lack of omega-3 increases the risk of cardiovascular disease

– whereas the often scolded cholesterol is good for you

Too many carbs and lack of omega-3 increases the risk of cardiovascular diseaseCardiovascular diseases account for more deaths than anything else. Still, there is a lot of discussion about the diet and its impact on cardiovascular health, typically when it comes to the question of avoiding fat and choosing margarine instead of butter. A team of Czech scientists decided to study diet habits among different populations and compare these with the risk of cardiovascular disease and premature death. Their study shows that there is no need to be afraid of cholesterol. In fact, the official dietary guidelines could easily do with an adjustment. At the same time, it is important to reduce our intake of carbohydrates and omega-6 fatty acids that are the real culprits. Finally, it is essential to increase the intake of omega-3.

Which dietary factors are the major global contributors to cardiovascular diseases?

Czech scientists wanted to take a closer look at that question, so they collected data about dietary habits in 158 different countries during the period 1993-2011. The data included the consumption of sixty different foods such as corn, meat, fish, eggs, dairy products, vegetables and fruit, plant oils, soft drinks, sugar, alcohol, tea, and coffee. The researchers also calculated the total calorie intake from carbohydrates, protein, and fats from animal and vegetable sources. It turned out that the dietary factor that contributes the most to the development of cardiovascular disease was a high carbohydrate intake, primarily carbohydrates from wheat and other corn products.
In contrast, the scientists discovered that the total intake of animal fat, animal protein, and vegetable protein was associated with a lower risk of developing cardiovascular disease. In other words, the more protein and animal fat in the diet, the lower the risk of cardiovascular disease and dying from blood clots caused by calcified arteries. Then again, there is a limit to how much protein we should consume.
The scientists also discovered that too much omega-6 from plant oils combined with too little omega-3 from oily fish increased the risk of hypertension and other cardiovascular diseases.

The results of the Czech population study indicate that what health authorities say about animal fat, cholesterol and plant oils does not square with reality.

Facts about cholesterol warning and manipulation with important data

The Czech study is published in the science journal Nutrients. In their introduction, the scientists explain that cholesterol warnings have become increasingly common and that they are not based on proper data. Warnings about cholesterol-loaded animal fats that cause cardiovascular disease were originally introduced in the United States in 1977 and in Great Britain in 1983.
After that, most other countries followed suit. The actual myth about saturated fat and how it raises blood cholesterol levels and causes atherosclerosis was presented in 1958 by the American doctor Ancel Keys with reference to his “Seven Countries Study”. Keys presented his studies of dietary habits in seven countries including Japan and the United States, claiming that he had found a relation between the intake of saturated fat, elevated cholesterol, hypertension, and cardiovascular disease. However, it turned out that the study had several flaws, as several of the included countries did not have registries with exact information about the different diagnoses. Moreover, Ancel Keys had excluded data from 15 countries that did not support his cholesterol hypothesis.
Later, a follow-up study from 1990 showed the exact opposite results in terms of blood levels of cholesterol and the risk of developing cardiovascular disease and dying prematurely. In fact, even when saturated animal fat was subsequently replaced with polyunsaturated plant oils, thereby lowering the amount of cholesterol in the blood, all-cause mortality went up during the same period. Interestingly, the results of this study did not get much publicity. On the contrary. The fear of cholesterol continued, and it is only fair to mention that there were and still are huge economic interests at stake within the agricultural and food industries, which manufacture corn and margarine, and within the pharmaceutical industry that manufactures cholesterol-lowering statins. Still, there are other factors involved in all the confusion about and debate over cholesterol and its impact on health.

High cholesterol is good – but not if you have metabolic syndrome or diabetes

Cholesterol is an essential compound that is found in all cell membranes. It supports the synthesis of vitamin D, coenzyme Q10, and sex and stress hormones. The liver produces the lion’s share of cholesterol from carbohydrate, and it is able to regulate its own cholesterol production. The more cholesterol one gets from the diet, the less the liver produces under normal circumstances.
According to the new Czech study, having high cholesterol levels in the blood (more than 5 nmol/L) lowers the risk of cardiovascular disease and premature death. High cholesterol levels appear to be good for you, and other studies have even shown that cholesterol supports the immune system and protects cells against carcinogens by strengthening the cell membranes.
On the other hand, having high cholesterol levels is not good if you have metabolic syndrome, including insulin resistance, hypertension, and too much abdominal fat. Metabolic syndrome is an early stage of type 2 diabetes and a sign of a disrupted glucose metabolism, where the liver produces too much cholesterol from excess amounts of carbohydrate in the blood. In these cases, it is essential to reduce one’s carbohydrate intake, as the carbohydrates are what cause the elevated cholesterol levels and the increased risk of cardiovascular disease. This certainly supports the new Czech study.

It appears that the 5 nmol/L threshold level for cholesterol in the blood is too low. People with elevated cholesterol levels generally live longer, unless they also suffer from metabolic syndrome or type 2 diabetes.

Cholesterol does not cause atherosclerosis, whereas inflammation does

Cholesterol is essential and is not harmful, unless it is attacked by free radicals that cause it to oxidize. Oxidized cholesterol is what is found on the inside of calcified vessel walls. The free radicals are aggressive molecules that occur naturally in the human body, but in the case that there are too many, it may result in oxidative stress and chronic inflammation, which is something that can easily go unnoticed.
The only thing that can protect us against free radicals and oxidative stress is the presence of antioxidants such as vitamins A, E, and C plus selenium, zinc, and a number of plant compounds.
It is also important to have an effective and properly balanced immune defense, where omega-3 and omega-6 fatty acids in the right balance are responsible for controlling inflammation. Consuming too much omega-6 and too little omega-3 sets the stage for chronic inflammation and conditions like atherosclerosis, cardiovascular disease, rheumatism, and a host of other ailments.
The Czech scientists observed how too much omega-6 from plant oils such as sunflower oil combined with too little omga-3 increased the risk of elevated blood pressure and other cardiovascular problems.
Moreover, polyunsaturated fatty acids such as omega-3 and omega-6 are vulnerable when exposed to high temperatures (frying and cooking) and tend to develop free radical and toxic aldehydes. It is therefore best not to use margarine when frying but butter or olive oil (omega-9) that is much more resistant to high temperatures.

Why do get more omega-6 and less omega-3 with modern diets?

Our consumption of margarine, sunflower oil, corn oil, grapeseed oil, ready meals, French fries, chips, cakes, and other types of junk food is the reason why we get far too much omega-6. Animal fodder also contains more omega-6, and that produces meat, farmed fish, dairy products and eggs with a much higher omega-6 content. Things are only made worse by the fact that people consume less fish, adding to their omega-3 deficiency. Diets in the Western world often contain omega-6 and omega-3 in a 10:1 ratio, where it should ideally be 4:1 or, better yet, 2:1.

How do we get enough omega-3?

There is big difference between omega-3 from vegetable and from animal sources. Vegetable sources such as linseed oil contain a form of omega-3 called ALA (alpha-linolenic acid), which is difficult for many people to utilize. Oily fish such as herring and salmon, on the other hand, contain the two omega-3 fatty acids EPA and DHA, which most people are able to utilize and that have anti-inflammatory properties.
It is best not to consume farmed fish but to choose fish from pristine ocean environments. Eat fish several times a week, and make sure to consume at least 200 grams of oily fish. For those who do not like the taste of fish or just don’t eat enough seafood, a fish oil supplement is a good alternative for a healthier cardiovascular system as well as for other health benefits. Fish oil based on free fatty acids has the best absorption. Make sure to buy a supplement that is within the threshold level in terms of peroxide value and content of environmental toxins.

Plea to the health authorities

As the Czech scientists see things, the warnings about saturated fat and cholesterol should never have been introduced. Instead, they argue for a shift of paradigm concerning diet recommendations and the underlying factors involved in cardiovascular disease.


Grasgruber P, Cacek J Hrazdira E et al. Global correlates of cardiovascular risk: a comparison of 158 countries. Nutrients 2018 Mar 26

Menotti A; Keys A et al. Twenty-year stroke mortality and prediction in twelve cohorts of the Seven Countries Study. Int. J. Epidemiol 1990

Harlan Krumholz. Inflammation: Is it the New Cholesterol? Pharma & Healthcare Medicine. August 2017

  • Created on .